21255652 has 24 divisors (see below), whose sum is σ = 40989312. Its totient is φ = 9564000.

The previous prime is 21255613. The next prime is 21255653. The reversal of 21255652 is 25655212.

21255652 = 99² + 100² + ... + 401².

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 21255652.

It is not an unprimeable number, because it can be changed into a prime (21255653) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2053 + ... + 6835.

It is an arithmetic number, because the mean of its divisors is an integer number (1707888).

Almost surely, 2^21255652 is an apocalyptic number.

21255652 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21255652 is a deficient number, since it is larger than the sum of its proper divisors (19733660).

21255652 is a wasteful number, since it uses less digits than its factorization.

21255652 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4899 (or 4897 counting only the distinct ones).

The product of its digits is 6000, while the sum is 28.

The square root of 21255652 is about 4610.3852333617. The cubic root of 21255652 is about 277.0074676400.

It can be divided in two parts, 2125 and 5652, that added together give a palindrome (7777).

The spelling of 21255652 in words is "twenty-one million, two hundred fifty-five thousand, six hundred fifty-two".